3/20/2009. Julio Garcia-Aguilar Chair, Department of Surgery City of Hope, Duarte, California

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1 Ischemic Colitis Ischemic Colitis Julio Garcia-Aguilar Chair, Department of Surgery City of Hope, Duarte, California Ischemic colitis (IC) represents greater than 50% of all intestinal ischemia IC most often affects the elderly 90% of case are in patients over 60 years old 1 Boley first described this condition in ) Binns et al. Gut )Boley et al Surg Gyn Obst 1963 Pathophysiolgy Predisposing Conditions Intestinal blood flow is inadequate to meet the metabolic demands of a region of the colon IC can be occlusive or non-occlusive is almost always non-occlusive Compromised blood flow may be secondary to changes in systemic circulation or local mesenteric (micro) vasculature Most cases involve watershed areas The rectum is usually spared due to dual blood supply Inferior mesenteric artery Internal ileac branches High blood pressure Cardiovascular disease Diabetes Chronic renal failure Chronic pulmonary disease Recent cardiovascular surgery Constipation/IBS?? 1

2 Risk Factors and Etiology Major vascular occlusion Mesenteric arterial thrombosis/embolus Mesenteric venous occlusion Micro-vascular disease Diabetes Rhumatoid arthritis Vasculitis Amyloidosis Radiation injury Hypo-perfusion CHF Transient hypotension Strenuous physical activities Shock Hypovolemia Septic Cardiac Koutroubakis et al. Gastroenterology 2001 Clotting disorders 1 Protein C/S deficiency Anti-thrombin III deficiency Factor V Leiden Sickle cell disease Anti-phospholipid syndrome Mechanical Obstruction Tumor Adhesions Volvuli Hernia Diverticulitis Prolapse Trauma Aortic Surgery 2-3% Medications associated with IC Antibiotics Appetite suppressants phentermine Chemotherapeutics vinca alkaloids Decongestants pseudoephedrine Digitalis Diuretics Ergot alkaloids Hormonal therapies Estrogen Danazol Statins Immunosuppressives Laxatives Nonsteroidal anti- inflammatory drugs Psychotrophic medications Serotonin agonist/antagonist vasopressors Illicit drugs Cocaine Blood Supply of the Colon Distribution of Disease Vasa Recta Marginal artery of Drummond Inferior mesenteric Artery Vasa Recta Marginal artery of Drummon Missing or incomplete in 5% of the population Left colon is involved in 75% of cases Splenic flexure 25% Isolated right colon ischemia 10%-26% More common in patients in shock Patients tend to have: Abdominal pain without bloody diarrhea More severe colitis 5 times more likely to need surgery Associated with worse outcome May be related to SMA occlusion and associated small bowel ischemia Flobert et al. Am J Gastro

Classification of Ischemic Colitis Clinical Presentation Gangrenous 15-20% Complete loss of arterial flow causes bowel wall infarction and gangrene, which can progress to perforation, peritonitis,

3 Classification of Ischemic Colitis Clinical Presentation Gangrenous 15-20% Complete loss of arterial flow causes bowel wall infarction and gangrene, which can progress to perforation, peritonitis, and death. Non-Gangrenous 80-85% Transient 50% Chronic 20% Stricturing 10% Transient, reversible impairment of the arterial supply, with accompanying reperfusion injury. Leads to partial mucosal sloughing that heals by mucosal regeneration in a few days. Gross impairment of the arterial supply, leading to hemorrhagic infarction of the mucosa. Heals by fibrosis, and can lead to stenosis Can lead to chronic segmental colitis No signs or symptoms are specific: Acute onset crampy abdominal pain Strong urge to defecate Bleeding: bright red or maroon diarrhea Profuse bleeding suggests another diagnosis Anorexia, nausea, or vomiting Elevated white blood cell count Dilation of the colon In gangrenous forms, symptoms and signs can progress rapidly Peritonitis Metabolic acidosis Signs of shock Diagnostic Strategy There are no specific laboratory markers of intestinal ischemia Lactate, LDH, CPK, amylase, alkaline phosphatase, etc. Need high index of suspicion based on history and co-morbidities physical exam Rule out Infectious colitis Pseudomembranous colitis Diverticulitis Colon carcinoma Imaging Abdominal plain films Thumbprinting submucosal hemorrhage and edema Air filled bowel loops Ileus Mural thickening Pneumatosis Portal venous air Free peritoneal air 3

Thumbprinting Ulcers Ridges Edema Strictures

Contraindicated if gangrenous ischemic colitis

be more difficult after barium enema Computed

transmural IC Mural thickening Thumbprinting

Double halo or target sign Submucosal edema &

Mesenteric vessel occlusion Transmural IC

4 Thumbprinting Ulcers Ridges Edema Strictures Barium Enema Eccentric mural deformity Contraindicated if gangrenous ischemic colitis because of the risk of perforation Endoscopy may be more difficult after barium enema Computed Tomography Often the initial test Non- transmural IC Mural thickening Thumbprinting Pericolonic fat stranding Peritoneal fluid Double halo or target sign Submucosal edema & hemorrhage Lack of bowel wall enhancement Mesenteric vessel occlusion Transmural IC Pneumatosis Portal venous air Free intra abdominal air Target Sign Pneumatosis and Portal Venous Air 4

Angiography Not typically part of the initial evaluation A treatable occlusive lesion is very rarely found Consider angiography if: Isolated right sided involvement Suggestion of SMA thrombosis

5 Angiography Not typically part of the initial evaluation A treatable occlusive lesion is very rarely found Consider angiography if: Isolated right sided involvement Suggestion of SMA thrombosis Colonoscopy Most common diagnostic method for IC Allows for visualization and biopsy Except for gangrene, neither visual findings nor histology are specific Serial studies may be necessary As opposed to IBD, IC often resolves in 1-2 weeks Colonoscopy Marked Erythema and Exudate Colonoscopic findings are suggestive but are not diagnostic Bulging folds from submucosal hemorrhage Ulcerations Friability Mucosal necrosis Segmental distribution Rectal sparing Sigmoidoscopy has a diagnostic accuracy of 92% and a negative predictive value of more than 94% Assadian et al. Vascular

Mucosal Edema, Exudates, and Ulcerations Severe IC with Pneumatosis Intestinalis Colonoscopy

Granularity Ulcerative colitis Crohn s colitis Ischemic colitis Infectious colitis Clinical

colitis Older age groups; vascular disease; sudden onset, often painful + stool cultures or

Segmental disease; rectal sparing; strictures, fissures, ulcers, fistulas; small bowel

6 Mucosal Edema, Exudates, and Ulcerations Severe IC with Pneumatosis Intestinalis Colonoscopy Differential Diagnosis In chronic IC other findings may include: Strictures Mucosal atrophy Granularity Ulcerative colitis Crohn s colitis Ischemic colitis Infectious colitis Clinical Bloody diarrhea Perianal lesions common; frank bleeding less frequent than in ulcerative colitis Older age groups; vascular disease; sudden onset, often painful + stool cultures or C-dif toxin Radiologic/Endoscopic Extends proximally from rectum; fine mucosal ulceration Segmental disease; rectal sparing; strictures, fissures, ulcers, fistulas; small bowel involvement Splenic flexure; thumb printing ; rectal involvement rare Diffuse colon wall thickening or toxic dilatation 6

Differential Considerations Atypical features in inflammatory bowel diseases Segmental distribution of the disease, infrequent rectal involvement High rate of spontaneous recovery, low rate of

7 Differential Considerations Atypical features in inflammatory bowel diseases Segmental distribution of the disease, infrequent rectal involvement High rate of spontaneous recovery, low rate of recurrence Lack of adequate response to usual inflammatory bowel disease therapy Frequent progression to fibrotic stenosis with delayed obstruction Now recognized as characteristic of colonic ischemia Always consider the diagnosis of ischemic colitis whenever contemplating the diagnosis of inflammatory bowel disease in an elderly patient Management Depends on clinical severity Most cases are transient and resolve spontaneously Mild cases require only supportive care NPO Broad spectrum antibiotics TPN if prolonged NPO Optimize cardiac function and oxygen delivery Serial abdominal exams Management Avoid vasopressors if possible Discontinue medications associated with colonic ischemia No bowel prep Avoid steroids Use volume aggressively treat low blood-flow states Most cases of non-occlusive ischemic colitis resolve in 2 to 4 weeks and do not recur Indications for Surgery Acute Ischemia Pneumoperitoneum Significant gangrenous IC on endoscopy Clinical deterioration despite conservative measures Peritonitis Sepsis without other source Persistent fever or leukocytes Persistent diarrhea, rectal bleeding or proteinlosing colopathy for more than 14 days 7

Surgery The goal is to remove all affect bowel with normal bowel at the margins Preoperative studies may help to guide the resection Looks for ischemia in the mucosa at the margin, not the serosa

8 Surgery The goal is to remove all affect bowel with normal bowel at the margins Preoperative studies may help to guide the resection Looks for ischemia in the mucosa at the margin, not the serosa Find pulsating vasa recta External appearance of the bowel may be normal at laparotomy Intraoperative Assessment Doppler vessels on the antimesenteric border Fluorescein 1 500mg of IV intra-operatively to evaluate colon viability with a woods lamp Look for uniform, patchy or absent illumination 1) Bergmen et al Ann Vasc Surg 1992 Chronic Ischemia Indications for Surgery Chronic segmental colitis with recurrent sepsis Symptomatic colonic strictures Suspicion of neoplasia Surgery Patient with acute ischemia: 33% had chronic renal failure 57% were receiving vasoactive drugs 56% had atherosclerosis 33% had an acute abdomen 51% of those died 54% were treated non-operatively initially 24% subsequently required surgery The overall mortality rate was 29% Scharf et al. Surgery

9 IC after Heart Surgery 3,724 pts with cardiac surgery 11 patients developed IC Risk factors: Lower ejection fraction; 45.1 vs. 49.7%, p <.01 Urgent cardiac operation; 3.49 times more likely to develop IC Mortality for pts with IC was 18% Predictors of Postoperative Mortality ASA (II,III) vs. (IV,V) 85 pt undergoing surgery for IC 50% had subtotal or total colectomy 80% had stoma formation OR 95% CI P value Elective/Emergency surgery EBL ( ) vs. (<300) Neither type of colectomy nor stoma formation impacted survival Vassiliou et al Cardiology 2008 Antolovic et al. Lengenbeck Arch. Surg 2008 Factors Associated with Worse Prognosis Age Absence of hematochezia Tachycardia Peritonitis Anemia Hyponatremia Colonic stenosis Conclusion IC has diverse etiology and presentation Gangrenous forms required urgent operation Right sided IC is associated with worse outcome Surgical resection is needed in a minority of cases but is associated with high mortality Operative planning based on both preoperative studies and intra-operative findings Normal serosa does not rule out IC Consider chronic IC in elderly patients with colitis Anon et al. World J of Gastro

Colon ischemia. Bible class 12 September Stefan Christen. ACG Clinical Guideline: Am J Gastroenterol 2015

Colon ischemia. Bible class 12 September Stefan Christen. ACG Clinical Guideline: Am J Gastroenterol 2015 Colon ischemia Bible class 12 September 2018 Stefan Christen ACG Clinical Guideline: Am J Gastroenterol 2015 Definition Definition Imbalance between blood supply and metabolic demands of the colonocytes